Resistor Color Code Calculator

Pick the band count for your resistor, then set each color band below — the resistance, tolerance range, and live resistor diagram update instantly.
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Resistor Color Code Calculator — 4, 5 & 6 Band

Decode resistance, tolerance, and temperature coefficient from color bands

Set your bands, then click Calculate
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Choose the color for each band on the left, then press Calculate to see the resistance, tolerance range, and decoded bands.
Color Digit Multiplier Tolerance Temp. Co.

Instant Decoding

Resistance, tolerance, and the resistor diagram all update live as you change any band — no button needed.

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4, 5 & 6 Band Support

Switch modes to decode standard, precision, or temperature-stable resistors with a third digit and tempco band.

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Built-in Reference

Expand the table to see every color's digit, multiplier, tolerance, and temperature coefficient value at a glance.

Understanding Resistor Color Codes

How to Read Resistor Color Bands

A complete guide to decoding 4-band, 5-band, and 6-band resistors

What Is a Resistor Color Code?

A resistor color code is a standardized system of colored stripes painted onto the body of a fixed resistor to indicate its resistance value, tolerance, and sometimes its temperature stability — without needing to print tiny numbers on a component that may be just a few millimeters long. The system was standardized internationally and is still the most common labeling method for axial-lead carbon-film and metal-film resistors used in everything from school electronics kits to industrial circuit boards.

Each band occupies a specific position and represents a specific piece of information. Reading them in the correct order, from the band closest to one end of the resistor toward the other, lets anyone identify the exact resistance and the manufacturer's guaranteed accuracy without a multimeter, a datasheet, or a magnifying glass — though a magnifying glass does help with very small components.

How the Bands Combine Into a Value

For a standard 4-band resistor, the first two bands are significant digits and the third is a multiplier:

Resistance = (10 × Digit1 + Digit2) × Multiplier
Digit1, Digit2 = 0–9 from the color chart  |  Multiplier = power-of-ten value of the third band  |  the fourth band gives tolerance only and does not affect the value

For example, Yellow-Violet-Red-Gold reads as 4, 7, ×100, giving (10 × 4 + 7) × 100 = 4,700 Ω, or 4.7 kΩ, with a tolerance of ±5%. On a 5-band or 6-band resistor, an extra digit band is inserted before the multiplier, so the formula becomes (100 × Digit1 + 10 × Digit2 + Digit3) × Multiplier, which allows three significant figures instead of two for tighter, more precise values such as 4.7 kΩ exactly rather than anywhere from 4.465 kΩ to 4.935 kΩ.

4-Band, 5-Band & 6-Band Resistors
Type 1
4-Band Resistor

The most common type: two significant digits, a multiplier, and a tolerance band. Typically rated ±5% (gold) or ±10% (silver), suitable for general-purpose circuits where exact precision isn't critical.

Type 2
5-Band Resistor

Adds a third significant digit for tighter precision, usually ±1% (brown) or ±2% (red) tolerance. Common in metal-film resistors used in audio equipment, measurement instruments, and precision analog circuits.

Type 3
6-Band Resistor

Identical to a 5-band resistor plus a sixth band showing the temperature coefficient in ppm/°C — how much the resistance drifts as temperature changes. Used where stability under heat matters, such as in precision reference circuits.

What Each Band Position Means
🔢 Significant Digit Bands

The first two (or three, on 5/6-band parts) bands form the base number of the resistance, read left to right starting from the band nearest either end of the resistor body.

✖️ Multiplier Band

This band scales the base number by a power of ten — or, for gold and silver, by a fraction (×0.1 or ×0.01) — to produce the final resistance in ohms.

🎯 Tolerance Band

Set slightly apart from the others (often with a small gap), this band states how far the actual resistance may legally deviate from the printed value — for example, a true 4.7 kΩ resistor with ±5% tolerance could measure anywhere from 4,465 Ω to 4,935 Ω.

🌡️ Temperature Coefficient Band

Found only on 6-band resistors, this final band specifies drift in parts per million per degree Celsius (ppm/°C) — a lower number means the resistor holds its value more steadily as it heats up.

5 Tips for Reading Resistor Bands Accurately
1
Find the tolerance band first — it's usually gold or silver and sits slightly separated from the rest, or closer to one edge, which tells you which end to start reading from.
2
Read left to right from the digit side — significant-digit bands are clustered together near one end, with the multiplier and tolerance trailing toward the other end.
3
Use good lighting — brown, red, and orange can look similar under poor light, and gold and yellow are easy to confuse on small components.
4
Verify with a multimeter when in doubt — color codes are a fast visual check, but a multimeter reading confirms the actual measured resistance, especially on aged or discolored components.
5
Remember the E-series — standard resistors are manufactured in preferred value series (E12, E24, E96), so a calculated value that doesn't match a standard value usually means a misread band.